Mario rolls a coin up a slope at 3 m/s North. It travels 8.3 m, comes to a stop and rolls back down.

When a metal is heated, the free electrons gain _____________.

evablogger [386]

<h2>Answer: C. Kinetic energy</h2>

Explanation:

Heat is energy in transit, in fact it is a transfer of thermal energy from one body to another.

So, when a metal is heated is because we have two bodies with different temperatures and thermal energy is transferred from one body to another, implying a high speed and kinetic energy in the particles involved (electrons in this case).

This is because the kinetic energy of a particle is that energy it possesses due to its movement, and according to the first principle of thermodynamics, there is a relationship between heat and movement, since the metal is composed of particles that are in motion (to a certain extent).

In this way, with the increase of the temperature of the metal, there is an increase of the kinetic energy of its free electrons with a gain of velocity (movement), therefore a gain in kinetic energy.

5 0

3 years ago

A particle initially located at the origin has an acceleration of = 1.00ĵ m/s2 and an initial velocity of i = 6.00î m/s. (a) Fin

Ira Lisetskai [31]

Answer:

a) d = (6.00 t i ^ + 0.500 t²) m , b) v = (6.00 i ^ + 1.00 t j ^) m / s

c) d = (24.00 i ^ + 8.00 j^ ) m , d) v = (6.00 i ^ + 5 j^ ) m/s

Explanation:

This exercise is about kinematics in two dimensions

a) find the position of the particle on each axis

X axis

Since there is no acceleration on this axis, we can use the relation of uniform motion

v = x / t

x = v t

we substitute

x = 6.00 t

Y Axis

on this axis there is an acceleration and there is no initial speed

y = v₀ t + ½ a t²

y = ½ at t²

we substitute

y = ½ 1.00 t²

y = 0.500 t²

in vector position is

d = x i ^ + y j ^

d = (6.00 t i ^ + 0.500 t²) m

b) x axis

as there is no relate speed is concatenating

vₓ = v₀

vₓ = 6.00 m / s

y Axis

there is an acceleration and the initial speed is zero

$v_{y}$ = v₀ + a t

v_{y} = a t

v_{y} = 1.00 t

the velocity vector is

v = vₓ i ^ + v_{y} j ^

v = (6.00 i ^ + 1.00 t j ^) m / s

c) the coordinates for t = 4 s

d = (6.00 4 i ^ + 0.50 4 2 j⁾

d = (24.00 i ^ + 8.00 j^ ) m

x = 24.0 m

y = 8.00 m

d) the velocity of for t = 4 s

v = (6 i ^ + 1 5 j ^)

v = (6.00 i ^ + 5 j^ ) m/s

7 0

3 years ago

A power plant produces 1000 MW to supply a city 40 km away. Current flows from the power plant on a single wire of resistance 0.

nikitadnepr [17]

Answer:

Current = 8696 A

Fraction of power lost = $\dfrac{80}{529}$ = 0.151

Explanation:

Electric power is given by

$P=IV$

where I is the current and V is the voltage.

$I=\dfrac{P}{V}$

Using values from the question,

$I=\dfrac{1000\times10^6 \text{ W}}{115\times10^3\text{ V}} = 8696 \text{ A}$

The power loss is given by

$P_\text{loss} = I^2R$

where R is the resistance of the wire. From the question, the wire has a resistance of $0.050\Omega$ per km. Since resistance is proportional to length, the resistance of the wire is